Re: [PATCH] perf test: fix failing test cases on linux-next for s390

From: Arnaldo Carvalho de Melo
Date: Fri Jun 16 2023 - 17:46:32 EST


Em Fri, Jun 16, 2023 at 01:48:45PM -0700, Ian Rogers escreveu:
> On Fri, Jun 16, 2023 at 6:13 AM Arnaldo Carvalho de Melo
> <acme@xxxxxxxxxx> wrote:
> >
> > Em Fri, Jun 16, 2023 at 10:14:37AM +0200, Thomas Richter escreveu:
> > > In linux-next tree the many test cases fail on s390x when running the
> > > perf test suite, sometime the perf tool dumps core.
> > >
> > > Output before:
> > > 6.1: Test event parsing : FAILED!
> > > 10.3: Parsing of PMU event table metrics : FAILED!
> > > 10.4: Parsing of PMU event table metrics with fake PMUs: FAILED!
> > > 17: Setup struct perf_event_attr : FAILED!
> > > 24: Number of exit events of a simple workload : FAILED!
> > > 26: Object code reading : FAILED!
> > > 28: Use a dummy software event to keep tracking : FAILED!
> > > 35: Track with sched_switch : FAILED!
> > > 42.3: BPF prologue generation : FAILED!
> > > 66: Parse and process metrics : FAILED!
> > > 68: Event expansion for cgroups : FAILED!
> > > 69.2: Perf time to TSC : FAILED!
> > > 74: build id cache operations : FAILED!
> > > 86: Zstd perf.data compression/decompression : FAILED!
> > > 87: perf record tests : FAILED!
> > > 106: Test java symbol : FAILED!
> > >
> > > The reason for all these failure is a missing PMU. On s390x
> > > the PMU is named cpum_cf which is not detected as core PMU.
> > > A similar patch was added before, see
> > > commit 9bacbced0e32 ("perf list: Add s390 support for detailed PMU event description")
> > > which got lost during the recent reworks. Add it again.
> > >
> > > Output after:
> > > 10.2: PMU event map aliases : FAILED!
> > > 42.3: BPF prologue generation : FAILED!
> > >
> > > Most test cases now work and there is not core dump anymore.
> >
> > So you're not fixing 'perf test', that is just what detects the problem,
> > the part being fixed is the PMU code, so I'm rewriting the patch subject
> > to:
> >
> > [PATCH] perf pmu: Fix core PMU detection on s/390
> >
> > Have you bisected the problem to the first patch where this problem
> > appears?
>
> I suspect:
> https://lore.kernel.org/all/20230527072210.2900565-30-irogers@xxxxxxxxxx/
> 9d6a1df9b2ee ("perf pmus: Allow just core PMU scanning")
>
> Acked-by: Ian Rogers <irogers@xxxxxxxxxx>

I already pushed to perf-tools-next, but this acked/fixes is reachable
via the Link tag.

Thanks for checking and acking!

- Arnaldo

> Thanks,
> Ian
>
> > - Arnaldo
> >
> > > Signed-off-by: Thomas Richter <tmricht@xxxxxxxxxxxxx>
> > > Cc: Ian Rogers <irogers@xxxxxxxxxx>
> > > ---
> > > tools/perf/util/pmu.c | 2 +-
> > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
> > > index fe64ad292d36..6142e4710a2f 100644
> > > --- a/tools/perf/util/pmu.c
> > > +++ b/tools/perf/util/pmu.c
> > > @@ -1419,7 +1419,7 @@ void perf_pmu__del_formats(struct list_head *formats)
> > >
> > > bool is_pmu_core(const char *name)
> > > {
> > > - return !strcmp(name, "cpu") || is_sysfs_pmu_core(name);
> > > + return !strcmp(name, "cpu") || !strcmp(name, "cpum_cf") || is_sysfs_pmu_core(name);
> > > }
> > >
> > > bool perf_pmu__supports_legacy_cache(const struct perf_pmu *pmu)
> > > --
> > > 2.39.2
> > >
> >
> > --
> >
> > - Arnaldo

--

- Arnaldo